A NATURALIST IN BRAZIL 



hairs they involuntarily brush the pollen from the stamens as they 

 creep into the flowers ; it remains entangled in their fur, until, when 

 next they enter a flower, it is rubbed off upon the stigma. Many 

 insects, like the bees, even collect the pollen in special combs or 

 brushes on their legs or abdomens, or in special depressions on their 

 thighs, or "baskets," for they require the pollen as albuminous 

 nutriment for their brood. Flowers which surrender their pollen as 

 nourishment produce such an excess of it that plenty is left for 

 the purposes of fertilization. Pollen-eating beetles, which visit such 

 "pollen flowers" exclusively, are always dusted all over with pollen; 

 they cannot clean it all off, and carry it into other flowers. Certain 

 orchids offer, in the place of pollen, a sort of albuminous meal, 

 which they expose upon their underlips, as though on a dish. Other 

 orchids develop nutritive warts and swellings, and by such means 

 they have taken into their service insects which would be of no use 

 to other flowers, as they have no proboscis with which they could 

 suck nectar. 



The "nectar flowers," which offer sweetstuffs to their visitors, need 

 not be so prodigal of their pollen, and accordingly they produce 

 less. They can draw upon the hosts of suctorial insects. They special- 

 ize mostly in the quantity of the nectar offered, accordingly as they 

 wish to entice deep or moderate drinkers. The American orchid 

 Corianthes produces a most abundant supply of nectar. On the 

 "underlip" of this flower — namely, the petal which stretches down- 

 wards, and is slightly turned up again at the point — a little pocket 

 is hollowed out, and from two minute horns the nectar drips into 

 this pocket until it finally holds nearly an ounce of honey. 



Another means adopted by the flowers of restricting the circle 

 of their visitors is to place the nectaries in a special position. Any 

 part of the flower may secrete nectar, and by deepening the corolla 

 it may be made less easy of access. Many plants, and especially the 

 Umbelliferae, oflfer their nectar, as it were, on flat dishes, so that 

 beetles and such flies as visit flowers can alight and lick it up without 

 more ado. In other flowers, however, the petals coalesce to form 

 tubes of varying diameter, until at last only the long trunks of the 

 butterflies or moths can find admittance. In Brazil there is a Hawk- 

 moth whose trunk attains the enormous length of more than 

 8 inches, so that it is able to enter a corolla of corresponding depth, 

 which no other insect is able to plumb. In America the Humming- 

 birds also are enlisted for the work of fertilization, and special flowers 

 have been evolved which are adapted to their bills, and even to the 



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